JDO, GAE: Load object group by child's key
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by tiex
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Published on 2009-11-01T12:06:43Z
Indexed on
2010/04/24
16:53 UTC
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I have owned one-to-many relationship between two objects:
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class AccessInfo {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private com.google.appengine.api.datastore.Key keyInternal;
...
@Persistent
private PollInfo currentState;
public AccessInfo(){}
public AccessInfo(String key, String voter, PollInfo currentState) {
this.voter = voter;
this.currentState = currentState;
setKey(key); // this key is unique in whole systme
}
public void setKey(String key) {
this.keyInternal = KeyFactory.createKey(
AccessInfo.class.getSimpleName(),
key);
}
public String getKey() {
return this.keyInternal.getName();
}
and
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class PollInfo
{
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
private Key key;
@Persistent(mappedBy = "currentState")
private List<AccessInfo> accesses;
...
I created an instance of class PollInfo and make it persistence. It is ok. But then I want to load this group by AccessInfo key, and I am getting exception NucleusObjectNotFoundException. Is it possible to load a group by child's key?
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